Former Vice President Dick Cheney “personally” oversaw at least four briefings with members of Congress about the Bush administration’s interrogation program in an effort to maintain support for the torture of detainees in U.S. custody.

The briefings, part of a “secret” defense of the program Cheney began in 2005, were held as congressional oversight committees were threatening to investigate, or end the use of the interrogation methods, lawmakers and officials told The Washington Post.

Cheney’s advocacy of the use of waterboarding and warrantless wiretapping are certainly no secret, but his role in defending the program to lawmakers was undisclosed to the public until this time.

Documents delivered to Capitol Hill last month by the CIA listed every lawmaker briefed on the interrogation program since 2002, but made no mention of Cheney’s involvement in the meetings. For the briefings led by Cheney, intelligence committee members were told that information pertaining to the person who oversaw the meetings was “not available.”

During the briefings, Cheney “was adamant that the enhanced interrogations were needed to preserve national security,” two participants in the briefings told the paper, and when lawmakers questioned the legality of the program, “CIA briefers said that half of the agency’s knowledge about al-Qaeda’s plans and structure had been obtained through the interrogations.”